The Anatomy of the Human Peritoneum and Abdominal Cavity / Considered from the Standpoint of Development and Comparative Anatomy

by George S. Huntington

IV. Order: Sirenia.

Of the two living representatives of this remarkable mammalian order the dugong (Halicore) is described as possessing a single cæcum, while the cæcal pouch of Manatus americanus, the manatee, is symmetrically bifid at the extremity (Fig. 366).

Fig. 366.—Manatus americanus, American manatee. Ileo-colic junction and bifid cæcum. (Columbia University Museum, No. 673.)

V. Order: Cetacea.

In the majority of the whales the ileo-colic junction is simple without cæcum, as in Physeter, Delphinus, Monodon and Phocæna (Fig. 367).

Fig. 367.—Phocæna communis, porpoise. Ileo-colic junction. (Columbia University Museum, No. 1007.)

A few forms have a small cæcal pouch.